Platelet-to-lymphocyte ratio in advanced Cancer: Review and meta-analysis

Inflammation biomarkers have been introduced into clinical practice for risk-rating in treatment of patients with cancer. We aimed to confirm the prognostic role of platelet-to-lymphocyte ratio (PLR) as a powerful biomarker for patients with advanced cancer. A systematic literature search was conducted through PubMed, Embase and Web of Science databases for studies on advanced tumors. Research articles that analyzed the PLR and hazard ratios (HR) in patients with overall survival (OS) or progression-free survival (PFS) data were involved. Two authors assessed the eligibility of trials and extracted data independently. Meta-analyses were performed with random-effect models. Data heterogeneity was calculated with the I2 method. Thirty-three eligible cohort studies including 8215 patients were further analyzed. Elevated PLR was associated with reduced OS (HR = 1.45, 95% CI, 1.31–1.61, p